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IEEE specified protocols for Wireless networking

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									Protocols:
IEEE 802.11 The original 2.4 GHz wireless LAN protocol, but also includes infrared
communication too. Data rates available are 1 and 2 Mbps. The protocol uses the 2.4 to
2.5 GHz ISM (Industrial, Scientific, and Medical) band. IEEE 802.11 in the United Stares
allows the frequency band from 2400 to 2483.5 MHz. Modulation protocol is FHSS
(Frequency Hopping Spread Spectrum). The standard was modified on August 31, 2000
and now allows a maximum data rate of 10 Mbps.

IEEE 802.11a The standard specifies WLAN in the 5 GHz UNII (Unlicensed National
Information Infrastructure) and supports maximum a data rate of 54 Mbps and uses
OFDM (orthogonal frequency division modulation). The protocol also supports data rates
of 6, 9, 12, 18, 24, 36, and 48 Mbps. The 5 GHz UNII frequency band consists of 3 sub-
bands, each with a defined maximum output power. The lower frequency band consists
of 4 non-overlapping channels from 5,150 to 5,250 MHz with a maximum power level of
40 mW. The middle band goes from 5,250 to 5,350 MHz with a maximum transmit
power of 200 mW and also with 4 non-overlapping channels. The upper frequency band
again consists of 4 non-overlapping channels from 5,725 to 5,825 MHz with a maximum
output power of 800 mW.The Wi-Fi alliance certifies the products for interoperability
between manufacturers.

IEEE 802.11b This standard uses DSSS (Direct Sequence Spread Spectrum) and uses the
2.4 GHz ISM band and provides for maximum data rate of 11 Mbps and with fall-back to
5.5 Mbps. The standard is also backward compatible to IEEE 802.11 standard operating
at 1 or 2 Mbps. The 2400 to 2483.5 Mhz band is divided into 11 overlapping 22 Mhz
wide frequency bands. This means that at any one location, there are 3 non-interfering
bands which are channels 1, 6, and 11. The Wi-Fi Alliance (wireless fidelity) to assure
interoperability of products from one manufacturer to another in the same frequency
band. Wi-Fi Alliance certifies products for 802.11a, 802.11b, and 802.11g). The IEEE
802.11b standard was ratified in 1999.

IEEE 802.11g The standard uses the same 2.4 GHz frequency band as 802.11b. OFDM
(Orthogonal Frequency Division Modulation) is used with a maximum data rate of 54
Mbps with lower rates of 6, 9, 12, 18, 24, 36, and 48 Mbps. The standard is backward
compatible with 802.11b. Wi-Fi Alliance certifies the products so that they interoperable
between manufacturers. The standard was approved in June 2003.

IEEE 802.11af The standard is more correctly known as 802.3af and defines PoE or
power over ethernet. This feature is very useful for the powering of VoIP (Voice over
Internet Protocol) phones and WLAN access points with the same cable that is used for
the ethernet connection.

IEEE 802.11e The standard will define the standard for QoS or Quality of Service. QoS
is important for VoIP (Voice over Internet protocol) and video data streams and the
standard will give priority to this data. Standard approval is expected by September 2005.
IEEE 802.11h The standard defines the use of DFS (dynamic frequency selection) in the
802.11a 5 GHz WLAN band. DFS detects possible interference from other devices in the
area using the same frequency and switches to another frequency channel in order to
avoid interference. TPC (transmit power control) is used to adjust the WLAN access
point transmit power in order to minimize interference with other services.

IEEE 802.11i This standard is the new WLAN security standard approved June 2004.
The standard uses WPA2 (WI-Fi Protected Access) that corrects the problems associated
with WEP (Wired Equivalent Privacy). The standard also defines the use of AES
(Advanced Encryption Standard) for data encryption. AES will require a hardware
upgrade for access points due to the higher processor requirement.

IEEE 802.11k This the proposed standard that will allow more efficient use of WLAN
access points with dynamic control of channel frequency and or power level. Approval is
expected by June 2006.


IEEE 802.11n This standard is only in the approval process at this time. This proposed
standard uses MIMO (Multiple Input Multiple Output) and should allow data rates up to
200 Mbps. The standard would be an upgrade to IEEE 802.11a, IEEE 802.11b, and IEEE
802.11g. Approval is not expected before the end of 2008 or early 2009.

IEEE 802.11r The standard will allow for fast roaming, particularly for mobile and
wireless VoIP (Voice over Internet Protocol) phones. First approval is expected by
September 2006.

IEEE 802.1X This standard defines port access control and is used for both the wired
network and WLAN. The standard is typically used with a RADIUS (Remote
Authentication Dial-In User Service) application. A user is allowed access to the network
once authenticated.

IEEE 802.15.4 This is the wireless standard describing a wireless personal area network
or WPAN. IEEE 802.15.4 defines the PHY (physical or frequency definition) and MAC
(media access control) layer. The ZigBee Alliance defines network, security, and
application layers. The ZigBee standard is quite different from the other wireless LAN
specifications. The goal is for products that are low cost, low power consumption, have
high security for control and monitoring applications, e.g., home automation, and with
relatively low data rates, i.e., 250 Kbps. Typical products will be battery powered and
have long life. Frequency bands are 868 MHz, 915 MHz, and the 2.4 GHz ISM band. The
number of nodes in a network is essentially unlimited (> 65,000). The first ZigBee
compliant chips were certified in April 2005. Products should be available in late 2005.

IEEE 802.16e This is the new wireless standard that is designed to provide the last mile
or backhaul connection to the client. Most use will probably be in the rural areas where
DSL or cable modem connections are not available. Frequency range will be between 10
and 60 GHz for line-of-sight configurations and below 11 GHz for non line-of-sight.
Both licensed and license-free bands will be used. The standard will accommodate data
rates as high as 268 Mbps. The WiMAX Forum is promoting the IEEE 802.16 standard
and will certify equipment. The initial frequency bands to be approved will probably in
the 5 GHz band. The 3.4 to 3.6 GHz licensed band is also of high interest for outside US.
Frequency bands below 1 GHz are also of interest. Some of the analog TV channels that
will be abandoned in the switch to digital TV could become available. First equipment to
be available will be in the 3.5 GHz band and be available at the end of 2005 outside the
United States. Equipment for the US will probably be available by mid 2006.

								
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